Most of the new speed restrictions are temporary. That means its governed by the electronic speed limit signs. They reduce speeds during peak/rush times or weather and open it up as conditions warrant on the Autobahn.
None of my fave high speed sections have been affected at all.
As far as who is fast etc, that varies and is unpredictable. What is entertaining is Grandma in her tuned 3+liter TDI A6 Avant blowing you off the road LOL!
The best display of major speed Ive seen lately was a blue current model GT-R absolutely laying it down on a nice day, light traffic near my exit(I join the Autobahn in a speed open zone
, and a poor Cayman trying so hard to keep him in sight. The GT-R was magnificent and moving so fast. 300+kmph was my guess. Lucky lucky person enjoying life GT-R style that day.
45% of the Autobahn is unlimited currently.